Posterous theme by Cory Watilo

2.22 to 2.24

 

 

2.22 Plenary Answer

30 November 2010

15:19

·         Note that the positive and negative charges balance for each picture

·         Therefore the total charge is zero in each situation

 

 

 

2.23 answers

24 November 2010

10:39

·         2.23 recall that there are forces of attraction between unlike charges and forces of repulsion between like charges

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Charge on ball A

Charge on ball B

Electrostatic Force

Positive

Negative

Attract

Positive

Positive

Repel

Negative

Positive

Attract

Negative

Negative

Repel

 

 

 

 

2.24

24 November 2010

10:39

·         2.24 explain electrostatic phenomena in terms of the movement of electrons

·         Charge up a student with the Van der Graph generator

·         Why does their hair stand on end? 

·         Can you explain this in terms of the movement of electrons?

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Explanation

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·         The electrons on each hair repel the electrons on every other hair

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